Exhaust stack



FIG. 1 is a perspective view of an exhaust stack according to a firstembodiment of the invention;

FIG. 2 is a second perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a left view thereof;

FIG. 6 is a right view thereof;

FIG. 7 is a top view thereof;

FIG. 8 is a bottom view thereof;

FIG. 9 is a first cross-sectional view thereof, taken along line 9-9 inFIG. 3; and,

FIG. 10 is a second cross-sectional view thereof, taken along line 10-10in FIG. 3.

FIG. 11 is a perspective view of an exhaust stack according to a secondembodiment of the invention;

FIG. 12 is a second perspective view thereof;

FIG. 13 is a front view thereof;

FIG. 14 is a rear view thereof;

FIG. 15 is a left view thereof;

FIG. 16 is a right view thereof;

FIG. 17 is a top view thereof;

FIG. 18 is a bottom view thereof;

FIG. 19 is a first cross-sectional view thereof, taken along line 19-19in FIG. 13; and,

FIG. 20 is a second cross-sectional view thereof, taken along line 20-20in FIG. 13.

The broken line portion of the figures is included to show unclaimedsubject matter only and forms no part of the claimed designs.

CLAIM The ornamental design for an exhaust stack, as shown anddescribed.